Re: Additional options for Sync Replication

On Mon, Mar 28, 2011 at 12:05 PM, Heikki Linnakangas
<heikki(dot)linnakangas(at)enterprisedb(dot)com> wrote:
> On 28.03.2011 13:14, Simon Riggs wrote:
>>
>> On Mon, Mar 28, 2011 at 10:52 AM, Simon Riggs<simon(at)2ndquadrant(dot)com>
>>  wrote:
>>>
>>> You have no basis on which to prevent this.
>>
>> It's also already on the Open Items list, put there by you.
>>
>> Why is this even a discussion point?
>
> FWIW, I agree this is an additional feature that we shouldn't be messing
> with at this point in the release cycle.

There is an open item about what the UI is for sync commit/sync rep,
which is the subject of this patch.

> The 'apply' mode would be quite interesting, it would make it easier to
> build load-balancing clusters. But the patch isn't up to the task on that
> yet - the 'apply' status report is only sent after
> wal_receiver_status_interval fills up, so you get long delays.

Yes it's up to the task, you misread it. It will continue sending
replies while apply <> flush and then it will fall back to the
behaviour you mention.

> PS. you're missing some break's in the switch-statement in
> SyncRepWaitForLSN(), effectively making the patch do nothing.

OK, thanks.

--
 Simon Riggs                   http://www.2ndQuadrant.com/
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